Air-lift pump



Jan. 18, 1927. 1,614,765

R. H.- TUCKER AIR LIFT PUMP Filed April 1. 1925 Patented Jan. 18, 1927.

UNITED STATES RALPH H. TUCKER, OF LOS ANGELES, CALIFORNIA.

AIR-LIFT PUMP.

Application filed April 1, 1925.

This invention relates to improvements in air lift pumps, and isespecially an improvement over the pumps disclosed in my co-pendingapplications Serial No. 718,794

filed June 9, 1924, and Serial No. 741,242

filed October 2, 1924.

The primary object of this invention is to provide. an improved air liftpump which has means for discharging the exhaust air into the oil stringabove the pump and to provide means for establishingcommunicationbetween the exhaust passages and the interior of the well hole which isabove the.

7 view which will be made manifest in the following detailed descriptionand specifically pointed out in the appended claims, refer-I ence is hadto the accompanying drawings for an illustrative embodiment of theinvention, wherein:

Figure 1 is a vertical section through the pump, the plunger or pistonbeing shown at the top of its stroke;

Fig. 2 is a vertical section taken substantially on the line 22of Fig.1;

Fig. 3 a view similar to Fig. 1,- the piston shown at the bottom of itsstroke;

F i 4 is ahorizontal section taken sub stantially on the line 4-4' ofFig 1;

Fig. 5 is a horizontal section taken on the line 55 of Fig. 1; and

Fig. 6 is a horizontal section taken on the line 66 of Fig. 1.

Referring to the accompanying drawings wherein similar referencecharacters designate similar parts throughout, the oil string which issuspended within a well hole is designated at 10, and the air pipe forsupplying compressed air to the pump is indicated at 11. IUpon the lowerend of the oil string 10 there is threaded an exhaust shoe 12', whichadjacent its upper end is pro vided with a'tapered seat 13 for seating aclosure or head 14. Within the exhaust shoe 12 there isdisposed a sleeve15 which is held in spaced relation a an outer sleeve 16 of the shoe soas to form air passages 17.

Serial No. 19,847.

Adjacent the bottom of the exhaust shoe 12 it is reduced to permitsecuring a pipe 18, which may 'COIlStltlltG an anchor or gas trap or thelike. A lateral projection 19 is formed upon the exhaust shoeadjacentsits bottom and a tube 20 is threaded thereon, which tubeextends ulpwardly within the well to a point above t e fluid level. Acavity 22 is formed in the projection 19 and communicates with the tube20 and with an annular chamber 23which is formed within the shoe belowthe inner sleeve 15. The ex haust shoe has portions 24 between the innerand outer sleeves 15 and 16 blocked OH, and aperture 25 areformedltherein forming inlet passages for the oil to the pump. The heador closure 14 has bores 26 and 27 which communicate with each other,with the bores 26 disposed opposite the apertures 25. The lower end ofthe head 14 is of a reduced diameter and is threaded as at 28. A nipple29 is threaded onto the lower end of the head 14 and has a chamber 30formed therein, within which is disposed a coil spring 31. A buffermember 32 has portions disposed within the chamber 30 against the coilspring 31 and is held therein as by a gland 3.3. 7

The barrel 34 for the pump, which 'is dis posed about the nipple 29, isthreaded onto the lower end of the head 14. The lower end of the barrelis closed as by a plug 35 having a depression 36 in which is disposed -acoil spring 37. A buffer 38 has portions disposed within the depression36 against the coil spring and is maintained therein by a gland 39.Within the barrel 34 there are arranged two piston heads 40 and 41 whichare connected by a hollow stem 42 which is slidable about the nipple 29.The upper piston head 41 is threaded onto the stem 42 whereas thelowerend of the stem 42 is threaded onto the nipple 43 formed upon thelower piston head. The lower piston head has an aperture 44 extendinglongitudinally therethrough, which is enlarged adjacent its bottom, asindicated at 45.

A valve member 46 is enlarged adjacent its upper end, as at 47, and hasapertures 48 formed therein. The lower end of the valve member 46carries a head 49 adapted to seat upon the lower piston head 40. It willbe understood that the'valve member 46 is capable of reciprocating backand forth within the lower piston head 40 upon engagement with thebuffers 32 and 38. Apertures 51 are formed in the lower piston head 40and communicate with the enlarged chamber 45. Apertures '52 are formedin the barrel 34 opposite the apertures 51 and communicate with thechamber 23.

An annular plate 53 is disposed about the reduced lower end of the head14 and is slidable thereon. This plate is urged upwardly as by a coilspring 54 to serve as a check valve, permitting liquid to 'enter thebarrel of the pump through the bores 27 and prevent dischargetherethrough. Passages 55 are formed in the head 14 and communicate withthe air passages 17 in the exhaust shoe. These passages are controlledas by ball check valves 56. Bores 57 are formed in the head 14 atopposite sides thereof between the bores 27. These bores constitutedischarge passages from the barrel upwardly through the head. The plate53 has apertures formed therein which register with the bores 57. Uponthe top of the head 14 there is disposed a plate 58 which has aperturesformed therein registering with the discharge bores 57. The plate 58also has apertures, permitting the plate to pass down over the ballcheck valve cages which house the ball check valves 56. This plate isurged downwardly as by a coil spring 59 which is disposed about acoupling 60 connecting the air pipe 11 to the head. A bore 61, which isformed in the head, establishes communication between the air pipe 11and the nipple 29.

The operation, of the pump is as follows: Compressed air or gas isforced downwardly through the air pipe 11. It passes down wardlythrough. the coupling 60 and through thebore 61 in the head 14, andenters the chamber 30 in the nipple 29. The compressed air can passthrough the buffer 32 into the interior of the hollow stem 42. At thebeginning ofthe down stroke of the plunger, the valve member 46"is inclosed position so that the upper closed end of the valve member 46closes the aperture 44 formed in the lower piston head 40. The air'pressure, which is developed within the hollow stem 42, therefore forcesthe piston downwardly, it being understood that both the upper and lowerpiston heads 41 and 40 and the hollow stem 42 move downwardly together.When the lower end of the valve member 46 engages the buffer 38, thevalve member 46 will be caused to be lifted, so that the head 49 willclose the enlarged chamber 45, and the apertures 48 will establishcommunication between the interior of the hollow stem 42 and theinterior of the barrel 34, which is disposed below the lower piston head40. Air from the air pipe 11 is then caused to be admitted through thelower piston head 40 to its under side, so as to force the piston uponits upward stroke. It will be understood that upon the downward movementof the piston, the well fluid or oil will be caused to enter the barrelthrough the apertures 35 and the entrance bores 26 and 27 past the plate53 which serves as a check valve. When'the air from the air pipe 11 iscaused to be admitted to the under side of the piston, so as to forcethe piston upwardly, the plate 53 closes. The oil or well fluid, whichis disposed within the barrel 34 above the upper piston head41, isforced upwardl through the discharge passages 57 past the plate 58serving as a check valve. During the upward movement of the piston, thevalve member 46 is frictionally held in its uppermost position, namely,that in which the apertures 48 permit air to pass through the valvemember 46. When the valve member 46 engages the upper bufier 32, causingit to be forced downwardly, the aperture 44 is again closed. At the sametime the head 49 is removed from the lower piston head 40, permittingthe air which is within the barrel 34 below the lower piston head 40 toexhaust through the enlarged bore or aperture 45 through the apertures51 and-through the apertures 52 into the annular chamber 23. From theannular chamber.23 the exhaust air has two possible routes or passages,one of these is to pass upwardly through the apertures 17 through thepassages 55 past the ball check'valves 56 and into the oil string 10.The other possible route is to enter the cavity 22 and pass upwardlythrough the tube 20. The passage, which the exhaust air takes, dependsentirely upon the pressures developed,

If the formation is such that but a small quantity of gas is developedin the well above the fluid level, a very small gas pressure will bedeveloped in the well above the fluid, and consequently the exhaust airwill pass upwardly through the tube 20 into the interior of the wellabove the fluid, thus gaining the efficiency of a lower exhaustpressure, which was the purpose of the construction disclosed in myvco-pending application Serial No. 741,242. This exhaust air is causedto take such a path because of the weight of the fluid within the oilstring 10 bearing upon the ball check valves 56. The exhaust of theexhaust air into the well above the fluid builds up a pressure aboxe thewell fluid so that eventually this p'ressure, which is developed, isgreater than the pressure developed upon the ball check valves 56 at thebottom of the oil string 10; and when such a condition of affairs isestablished, the exhaust air will be forced upwardly past the ball checkvalves 56 and into the oil string. WVhere the formation is such that aconsiderable amount of gas pressure is developed above the well fluid oroil, this pressure frequently is sufficiently great to lift the columnof liquid in the oil string 10. Consequently, the gas because of itspressure can be forced downwardly through the tube into the chamber 23and can pass upwardly through the air passages 17 beneath the ball checkvalves 56 and escape into the oil string 10, so that the gas, whichflows, in this manner serves as an air lift for lifting the oil in theoil string. In such cases the exhaust air from the pump also passesupwardly through the air passages 17 and cooperates with the gas inlifting the oil in the oil string. The direction orroute which theexhaust air takes upon being discharged from the pump will thereforedepend entirely upon the condition of pressures developed at the variouslocations in the well.

From an inspection of Figs. 1 and 3, it will be readily understood thatthe apertures or exhaust ports 52 in the barrel-are never covered by thepiston heads 40 and 41.

The exhaust air passes from'below the lower piston head 40 into theannular chamber defined between the barrel 34 and the hollow stem 42,and it may discharge through the exhaust apertures 52 continuallyregardless of the positions of the piston or plunger of the pump. I

From the above it will be appreciated that an improved pump is providedwhich is of the reciprocating piston type and which is mounted upon thelower end of an oil string, which has conducting means for conductingthe exhaust air from the pump into the oil string, and that a tube isprovided which communicates with the conducting means, which tube alsocommunicates with theinterior of the well above the liquid leveltherein. In the improved form of pump construction, it will be notedthat the present type of pump employs a construction similar to thatdisclosed in my co-pending applications, but that the hollow stem 42,which heretofore was slidable within an air cylinder, is now slidableupon a nipple 'or conducting device, so that the interior of the hollowstem constitutes the air cylinder for forcing the piston downwardly.

It will be understood that various changes in the detail of constructionmay be made without departing from the spirit or scope of'the inventionas defined by the appended claims.

I claim: y

1. An air lift pump comprising a compressed air operated pumpingmechanism secured to an oil string, exhaust conducting means forconducting the exhaust air from the pump to the oil string, and meansconnectlng the exhaust conducting means with the interior of the wellabove the fiuid level as and for the urpose described.

2. An air lift pump comprising an oil string, an air pipe disposedwithin the 'oil string, a barrel connected with the oil string, a pistonhaving an opening therethrough and being reciprocable in said barrel,conducting means providing a connection between the air pipe and thepiston, means for alternately opening and closing said conducting meanswhereby the piston may be forced downwardly by the air when theconducting means is.closed and may then be forced upwardly by the airwhen the conducting means is open, means includin check valves foradmitting oil to the barrei means including check valves fordischarging. the oil from the barrel into the oil string, exhaustconducting means for conducting the exhaust air from below the piston tothe oil string, and means establishing communication between the exhaustconducting means and the interior of the well above the liquid level.

3. An air lift pump comprising an oil string, a barrel mounted upon theoil string, a head closing the upper end of the barrel, an air pipedisposed within the oil string, means including a nipple forestablishing communication between the air pipe and the interior of thebarrel, a stem disposed about said nipple and slidable thereon, a pistonhead mounted upon said stem having an aperture communicating with theinterior of said stem, means for opening and closing said aperturecausing reciprocation of said piston, a second piston head mounted uponthe upper end of said stem, means including check valves for admittingfluid to said barrel above the second pistonhead, means including checkvalves permitting the fluid to be forced through said head from the.barrel into the oil string, and exhaust conducting means for conductingexhaust air from said barrel.v

4:. An air lift pump comprising an oil string, a barrel mounted upon the011 string,

a head closing the upper end of the barrel, an air pipe disposed withinthe oil string, means including a nipple. for establishing communicationbetween the air pipe and the interior of the barrel, a stem. disposedabout said nipple and slidable thereon, a piston head mounted upon saidstem having an aperture communicating with the interior of said stem,means for opening and closing said aperture causing reciprocationof saidpiston, a second piston head mounted upon the'upper end of said stem,means including check valves for admitting fluid to said barrel abovethe second piston head, means including check valves permitting thefluid to be forced through said head from the barrel into the oilstring, and exhaust conducting means for conducting exhaust air fromsaid barrel into the oil string.

5. An air lift'pump comprising an oil string,-a barrel mounted upon theoil string,

a head closing the upper end of the barrel,

piston, a second piston head mounted upon the upper end of said stem,means including check valves for admitting fluid to said barrel abovethe second piston head, means including check "alves permitting thefluid to bev forced through said head from the barrel into the oilstring, and exhaust conducting means for conducting exhaust air fromsaid barrel into the open Well above the Well fluid.

(ifAn air lift pump comprising an oil string, a barrel mounted upon theoil string, a head closing the upper end of the barrel, an air pipedisposed within the oil string, means including a nipple forestablishing communication between the air pipe and the interior of thebarrel, a stem disposed about said nipple and slidable thereon, a pistonhead mounted upon said stem having an aperture communicating with theinterior of said stem, means for opening and closing said aperturecausing reciprocation of said piston, asecond piston head mounted uponthe upper end of said stem, means including check valves for admittingfluid to said barrel above the second piston head, means including checkvalves permitting the fluid an air pipe disposed within the oilstring, 1

means including a nipple for establishing communication between the airpipe and the interior of the barrel, a stem disposed about said nippleand slidable thereon, a piston head mounted upon said stem having anaperture communicating with the interior of said stem, means for openingand closing said aperture causing reciprocation of said piston, a secondpiston head mounted upon the upper end of said stem, means includingcheck valves for admitting fluid to said barrel above the second pistonhead, means including check valves permitting the fluid to beforced'through said head from the barrel into the oil string, an exhaustshoe disposed about said barrel, means including check valves for'conducting exhaust air from the barrel through the exhaust shoe anddischarging it into the oil string, and a tube extending upwardly withinthe well above'the well fluid and communicating withv said exhaust shoe.

In testimony whereof I have signed my name to this specification.

RALPH H. TUCKER.

